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1.
Animals (Basel) ; 13(4)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36830401

RESUMO

Light presents an important exogenous factor for poultry. This study examined effects of LED lights with different defined spectrums on growth and reproduction of indigenous Beijing-You chickens. A total of 576 one-day old female chicks were divided into 16 rooms, and each were exposed to four different lights: LED A (21% green light, 30% blue light, 24% yellow light, and 25% red light), B (35%, 35%, 18%, and 12%), C (27%, 30%, 22%, and 21%), or compact fluorescent lamps (CFL, 15%, 28%, 41%, and 16%). Results showed that feed intake and feed conversion ratio were comparable among treatments throughout the 17 week rearing period (p > 0.05). LED C showed similar body weight gain with CFL, but higher than LED A and B. The CFL birds start to lay on 132.25 d, while LED B did not lay until 148.25 d. The age at 50% egg production did not vary among groups (p = 0.12). Total egg number until 43 week of LED B was higher than others (p < 0.05). Therefore, LED lights with defined spectral proportion have different effects on chickens' growth and reproduction. The LED C promotes the prepubertal growth, and the LED B provides proper sexual maturation age and better egg-laying persistence.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33405994

RESUMO

A rapid, sensitive and species preservative analytical method for the simultaneous determination of six selenium (Se) species has been developed. Enzymatic probe sonication (EPS) was investigated as a novel and alternative technology for the extraction of Se species from feed matrices and the results were compared with the conventional hot water extraction, enzymatic hydrolysis and sequential extraction. The critical parameters of EPS such as enzyme types, extraction time, temperature, ultrasonic power and sample/enzyme ratio were varied with control. The Se species were separated and quantitatively determined by ion chromatography-inductively coupled plasma mass spectrometry (IC-ICP-MS). Under current optimised conditions, six inorganic and organic Se species were completely separated within 15 min in a single chromatographic run. The spectral interferences from the argon plasma 40Ar2, 40Ar37Cl or 1H79Br were effectively removed by employing the kinetic energy discrimination (KED) mode. Quantitative extraction for total Se (>94.8%) and more than 89.0% for the sum of different Se chemical forms without species transformation were obtained in only 60 s by applying the EPS treatment using aqueous protease XIV. The limits of detection (LODs) and quantification (LOQs) for Se species were in the ranges of 0.21-0.56 µg kg-1 and 0.69-1.87 µg kg-1, respectively. The proposed method was successfully applied to the speciation of Se in several reference materials and feed samples collected from the markets and local farms.


Assuntos
Análise de Alimentos , Contaminação de Alimentos/análise , Pronase/metabolismo , Selênio/análise , Sonicação , Hidrólise , Espectrometria de Massas , Selênio/metabolismo , Streptomyces griseus/enzimologia
3.
PeerJ ; 8: e9147, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32461835

RESUMO

Cow mastitis is a major problem frequently encountered by dairy farmers and it is manifested by the high number of somatic cells and the low quality of the milk. The conventional treatment for mastitis is use of antibiotics. In the current study, a new approach is applied to target this disorder: rumen bypass melatonin feeding (RBMF). The RBMF significantly reduced milk somatic cell count and improved milk nutritional values with the elevated protein, fat and dry matter levels. This approach also suppresses the stress and proinflammatory responses of the cows indicated by the reduced serum cortisol, TNF-α and IL-6 and increased IL-10 levels. Importantly, the beneficial effects of RBMF have lasted for several days after termination of the treatment. The effects of melatonin on the mastitis are probably attributed to the antioxidant and anti-inflammatory activities of melatonin. Considering the none or low toxicity of melatonin to organisms and the no invasive nature of this approach, we recommend that RBMF could be used in large scale in the dairy farming to target the cow mastitis.

4.
Asian-Australas J Anim Sci ; 31(8): 1259-1266, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29381894

RESUMO

OBJECTIVE: This study was carried out to investigate the possible application of Broussonetia papyrifera (B. papyrifera) silage as a functional feeding stuff in dairy cattle. METHODS: Seventy-two Holstein cows were divided into four groups randomly and allocated to 6 pens with 3 individuals in each group and fed the original total mixed ratio (TMR) in the dairy farm or the new TMR with 5%, 10%, and 15% B. papyrifera silage, separately. Feed intake were recorded, milk and blood samples were collected, and milk composition, blood metabolites and milk fatty acids composition were measure at the end of the experiment. RESULTS: Dry matter intake of cows decreased when they fed on diet with B. papyrifera, but no differences were observed in body condition score, milk yield, milk protein and lactose, feed efficiency and serum metabolites between groups. Both 10% or 15% of B. papyrifera silage in the diet significantly increased the immunoglobulin A (IgA) and IgG in serum, 15% of B. papyrifera silage increased the content of serum catalase, superoxide dismutase, total antioxidant capacity, and decreased the content of 8-hydroxy-2'-deoxyguanosine. Furthermore, 10% or 15% of B. papyrifera silage resulted in a significant decrease in the milk somatic cell count, and increased the polyunsaturated fatty acids content in the milk. CONCLUSION: The diets with 10% to 15% of B. papyrifera silage might enhance the immune and antioxidant function of dairy cows and increase the polyunstaturated fatty acid concentration in the milk.

5.
J Chromatogr A ; 1530: 51-58, 2017 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-29169645

RESUMO

Enzymatic probe sonication (EPS) was investigated as a novel and alternative technology for the extraction of five Se species SeCys2, MeSeCys, Se (IV), SeMet and Se (VI) from animal feeds. The critical parameters of EPS such as enzyme types, ultrasonic power, sample/enzyme ratio, extraction time and temperature were carefully optimized. Under current conditions, one sample can be extracted in 60s, in contrast to several hours required by the conventional enzymatic methods Moreover, the extraction is performed in pure water, no further temperature control or pH adjustment is needed, and therefore the risk of species interconvertion is drastically reduced or inhibited. The Se species were separated and quantitatively determined by high-performance liquid chromatography-hydride generation atomic fluorescence spectrometry (HPLC-HG-AFS), which allows the separation of organic and inorganic Se species in a single chromatographic run. The newly developed method was successfully applied to the determination of Se species in 18 feed samples collected from markets and local farms. Concerning the feed samples studied, the results of this work suggest that stricter measures should be taken to control the Se-enriched feed supplements in terms of Se species.


Assuntos
Ração Animal/análise , Análise de Alimentos/métodos , Selênio/química , Sonicação , Animais , Cromatografia Líquida de Alta Pressão , Suplementos Nutricionais/análise , Selênio/análise , Selenometionina/análise , Água/química
6.
Anim Nutr ; 1(4): 349-355, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29766995

RESUMO

This study investigated the effects of protein sources for milk replacers on growth performance and serum biochemical indexes of suckling calves. Fifty Chinese Holstein bull calves with similar BW and age were randomly allocated to 5 groups (1 control and 4 treatments) of 10 calves in each group. Five types of milk replacers were designed to have the same level of energy and protein. The protein source for milk replacers of the control group was full milk protein (MP). The protein source of milk replacers of the 4 treatment groups was composed of MP and one vegetable protein (VP) (30 and 70% of total protein). The 4 types of VP were soybean protein concentrate (SP), hydrolyzed wheat protein (WP), peanut protein concentrate (PP), and rice protein isolate (RP). Results of the experiment showed: 1) there was no significant difference on average daily gain (ADG) and feed:gain ratio (F:G) among the MP, SP and RP groups (P > 0.05), whereas the ADG and F:G of the WP and PP groups were significantly lower compared with the MP group (P < 0.05); 2) there was not a significant difference in withers height, body length and heart girth among treatment groups compared with the MP group (P > 0.05). Thereby the 4 VP milk replacers had no adverse effects on body size of calves; 3) all groups showed no significant difference in the serum contents of urea nitrogen, total protein, albumin, globulin, ß-hydroxybutyrate, growth hormone, insulin-like growth factor-1, and the ratio of albumin to globulin (A:G) (P > 0.05). In conclusion, SP or RP (accounts for 70% of the total protein) as calf milk replacers could substitute MP, whereas wheat gluten and PP had a significant adverse effect on growth performance in this experiment.

7.
Mol Biol Rep ; 41(2): 909-14, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24385298

RESUMO

Ghrelin, an endogenous ligand for growth hormone secretagogue receptor, plays an important role in stimulating hormone secretion, development of gastrointestinal tract, food intake and regulating energy balance of animals. In this study we isolated the cDNA sequence of ovine Ghrelin from the abomasums of 7-day-aged lambs. Real-time PCR was used to determine the abundance of Ghrelin mRNA in lamb gastrointestinal tract, and analyze the development changes of abomasums Ghrelin mRNA expression in 0-56 days lambs, as well as find the effects of 42-day weaning on Ghrelin mRNA expression in lamb abomasums. The results showed that: (1) Ghrelin mRNA was expressed widely in gastrointestinal tract and was significantly higher in the abomasums than in other tissues (rumen, reticulum, omasum, duodenum, jejunum, ileum) (P < 0.01); (2) The expression of abomasums Ghrelin mRNA in lamb increased with the growth of age, it reached a plateau at the age of 49 days, however, got a slightly decrease at the age of 56 days; (3) The expression of abomasums Ghrelin mRNA of the 42 days-weaned groups were significantly lower than the no-weaned groups (P < 0.05), and the Ghrelin mRNA expression of the two treatments reached a maximum at the age of 49 days; (4) Correlation analysis indicated that the linear correlativity between abomasums Ghrelin mRNA expression and abomasums weight was very prominent (R(2) = 0.647, P = 0.009). Our results suggested that ovine Ghrelin gene may play an important role in the development of lamb abomasums and 42-day weaning could down regulate the expression of abomasum Ghrelin mRNA, but the mechanism of these needs further research.


Assuntos
Trato Gastrointestinal/metabolismo , Grelina/biossíntese , Receptores de Grelina/genética , Desmame , Animais , Peso Corporal , Duodeno/metabolismo , Ingestão de Alimentos , Regulação da Expressão Gênica , Grelina/genética , Masculino , Omaso/metabolismo , RNA Mensageiro/biossíntese , Receptores de Grelina/metabolismo , Rúmen/metabolismo , Carneiro Doméstico/genética
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